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A Léonard G Decat E D Léonard A Wambersie J Renard 《Strahlentherapie und Onkologie》1987,163(12):795-799
Peripheral blood lymphocytes of patients undergoing radiation therapy for pelvic tumours have been examined for the presence of dicentric and centric ring chromosomes. Blood samples were taken, by venipuncture, prior to the first radiotherapy session and 24 h after radiotherapy sessions to allow the mixing of the irradiated lymphocytes in the circulating blood. The yield of dicentrics and centric rings was best fitted by a straight line which, according the maximum likelihood method, corresponds to Y = 1.77 +/- 0.0003 10(-2) D. On this basis the dose inducing ten dicentrics or rings is 5.62 Gy at the target volume and, thus, is intermediate between the doses at the target volumes displaying the same effects in patients treated for mammary carcinoma (15 Gy) or for ankylosing spondylitis (2 Gy). 相似文献
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A Sultan C Piot D Mariano-Goulart J P Daures F Comte E Renard A Avignon 《Diabetic medicine》2006,23(4):410-418
AIMS: To assess the association between abnormal stress myocardial perfusion imaging (MPI) and cardiac events (CE) in asymptomatic patients with diabetes and with > or = 1 additional risk factor. Predictors of abnormal stress MPI were also evaluated. METHODS: Four hundred and forty-seven consecutive patients who underwent stress MPI were prospectively followed for 2.1 [0.5-4.1] years for the subsequent occurrence of hard CE (myocardial infarction and sudden or coronary death) and soft CE (unstable angina and ischaemic heart failure requiring hospitalization). Re-vascularization procedures performed as a result of the screening protocol were not included in the analysis. RESULTS: Follow-up was successful in 419 of 447 patients (94%), of whom 71 had abnormal MPI at baseline. Medical therapy was intensified in all subjects and especially in those with abnormal MPI. Twenty-three patients with abnormal MPI underwent a re-vascularization procedure. CEs occurred in 14 patients, including six of 71 patients (8.5%) with abnormal MPI and eight of 348 patients (2.3%) with normal MPI (P < 0.005). Only two patients developed a hard CE and 12 a soft CE. In multivariate analysis, abnormal MPI was the strongest predictor for CEs [odds ratio (OR) (95% CI) = 5.6 (1.7-18.5)]. Low-density lipoprotein cholesterol > or = 3.35 mmol/l [OR (95% CI) = 7.3; 1.5-34.7] and age > median [OR (95% CI) = 6.0 (1.2-28.6)] were additional independent predictors for CE. The independent predictors for abnormal MPI were male gender, plasma triglycerides > or = 1.70 mmol/l, creatinine clearance < 60 ml/min and HbA1c > 8%, with male gender the strongest [OR (95% CI) = 4.0 (1.8-8.8)]. CONCLUSIONS: Asymptomatic patients with diabetes in this study had a very low hard cardiac event rate over an intermediate period. This could be explained by the effects of intervention or by the low event rate in the background population. Randomized studies of cardiac heart disease screening are required in asymptomatic subjects with diabetes to determine the effectiveness of this intervention. 相似文献
5.
F. Estelle R. Simons on Behalf of the Early Prevention of Asthma in Atopic Children Study Group 《Pediatric allergy and immunology》2007,18(6):535-542
There are more than 40 H(1)-antihistamines available worldwide. Most of these medications have never been optimally studied in prospective, randomized, double-masked, placebo-controlled trials in children. The aim was to perform a long-term study of levocetirizine safety in young atopic children. In the randomized, double-masked Early Prevention of Asthma in Atopic Children Study, 510 atopic children who were age 12-24 months at entry received either levocetirizine 0.125 mg/kg or placebo twice daily for 18 months. Safety was assessed by: reporting of adverse events, numbers of children discontinuing the study because of adverse events, height and body mass measurements, assessment of developmental milestones, and hematology and biochemistry tests. The population evaluated for safety consisted of 255 children given levocetirizine and 255 children given placebo. The treatment groups were similar demographically, and with regard to number of children with: one or more adverse events (levocetirizine, 96.9%; placebo, 95.7%); serious adverse events (levocetirizine, 12.2%; placebo, 14.5%); medication-attributed adverse events (levocetirizine, 5.1%; placebo, 6.3%); and adverse events that led to permanent discontinuation of study medication (levocetirizine, 2.0%; placebo, 1.2%). The most frequent adverse events related to: upper respiratory tract infections, transient gastroenteritis symptoms, or exacerbations of allergic diseases. There were no significant differences between the treatment groups in height, mass, attainment of developmental milestones, and hematology and biochemistry tests. The long-term safety of levocetirizine has been confirmed in young atopic children. 相似文献
6.
The rate of heat storage mediates an anticipatory reduction in exercise intensity during cycling at a fixed rating of perceived exertion 总被引:8,自引:2,他引:6
Ross Tucker Trevor Marle Estelle V. Lambert Timothy D. Noakes 《The Journal of physiology》2006,574(3):905-915
The aim of the present study was to examine the regulation of exercise intensity in hot environments when exercise is performed at a predetermined, fixed subjective rating of perceived exertion (RPE). Eight cyclists performed cycling trials at 15°C (COOL), 25°C (NORM) and 35°C (HOT) (65% humidity throughout), during which they were instructed to cycle at a Borg rating of perceived exertion (RPE) of 16, increasing or decreasing their power output in order to maintain this RPE. Power output declined linearly in all three trials and the rate of decline was significantly higher in HOT than in NORM and COOL (2.35 ± 0.73 W min−1 , 1.63 ± 0.70 and 1.61 ± 0.80 W min−1 , respectively, P < 0.05). The rate of heat storage was significantly higher in HOT for the first 4 min of the trials only, as a result of increasing skin temperatures. Thereafter, no differences in heat storage were found between conditions. We conclude that the regulation of exercise intensity is controlled by an initial afferent feedback regarding the rate of heat storage, which is used to regulate exercise intensity and hence the rate of heat storage for the remainder of the anticipated exercise bout. This regulation maintains thermal homeostasis by reducing the exercise work rate and utilizing the subjective RPE specifically to ensure that excessive heat accumulation does not occur and cellular catastrophe is avoided. 相似文献
7.
Site selection for fat autotransplantation: Some observations 总被引:4,自引:0,他引:4
The use of autologous fat for implantation has recently received renewed attention in the plastic surgery literature. Autologous fat reportedly has been used for the treatment of wrinkles and Romberg's disease, and for buttock and breast augmentation. While some measure of success has been achieved, many surgeons report that substantial resorption of fat tissue occurs at the site of implantation. There is lack of unanimity regarding the ideal site for extraction or injection in order to minimize fat resorption. Adipose tissue samples were taken from women undergoing surgical procedures on the abdomen, gluteal-femoral region, and breast. Facial adipose tissue samples from men and women were also analyzed. Adipocytes were isolated chemically and sized microscopically. Activity of the lipogenic enzyme adipose tissue lipoprotein lipase (ATLPL) was measured in frozen samples. Results suggest that femoral site samples are somewhat larger (NS) and have greater lipogenic activity (p<0.03) than other sites. In our study, small facial samples had very low or unmeasurable levels of ATLPL activity. Perhaps cell size and lipogenic activity should be considered when selecting tissues for autotransplantation. 相似文献
8.
Andrew P. Thomas Dennis J. Rozanski Dominique C. Renard Emanuel Rubin 《Alcoholism, clinical and experimental research》1994,18(1):121-131
Chronic ethanol consumption leads to a number of alterations in the contractile function of the heart and is a leading cause of cardiomyopathy. Ethanol also has an acute negative inotropic effect mediated by direct interaction with cardiac muscle cells, although this action is often masked by indirect actions resulting from enhanced release of catecholamines in vivo. This article reviews the effects of ethanol on the contractile function of the heart. The specific targets affected by ethanol in cardiac muscle cells are discussed in terms of potential mechanisms underlying the depressions of contractility resulting from both acute and chronic actions of ethanol. 相似文献
9.
G Stoter A Akdas S D Foss? S B Kaye C J van Groeningen J Renard M van Glabbeke 《Annals of oncology》1992,3(7):577-578
Eighteen patients with progressive disseminated, platinum-resistant germ cell tumors were treated with epirubicin 135 mg/m2, every 3 weeks. One patient had stable disease, 17 developed progression. Myelosuppression was dose-limiting. One patient died of neutropenic septicemia. High-dose epirubicin is not active against platinum-resistant germ cell cancer. 相似文献
10.
P Damas A Adam J Buret C Renard M Lamy J B Foidart P Mahieu 《European journal of clinical investigation》1987,17(2):166-173
An enzyme-linked immunoassay has been recently set up for direct measurement of the binding capacity of plasma fibronectin to gelatin. This binding capacity could be completely inhibited in vitro by an eight-fold excess of gelatin, of Haemaccel, but not of Geloplasma. On the contrary, the levels of immunoreactive fibronectin measured by laser nephelometry did not change, in presence of 10 to 1000 micrograms ml-1 of gelatin, of Haemaccel or of Geloplasma. When infused into normal volunteers, Haemaccel provoked a strong and immediate inhibition of the plasma fibronectin binding capacity to gelatin. This inhibition was dose-dependent and maximal after infusion of 500 ml of Haemaccel. Twenty-four hours after this infusion, there was a progressive recovery of the gelatin-binding capacity, which was almost completely achieved 96 h later. The formation of complexes between Haemaccel and fibronectin was demonstrated by gel filtration chromatography and by affinity chromatography. Immunoreactive plasma fibronectin levels remained unchanged up to 24 h after infusion of 500 ml of Haemaccel. A transient decline to 50% of its initial value then occurred the second day after the infusion. Therefore, a delay existed between the formation of fibronectin-Haemaccel complexes and their elimination from the bloodstream. This delay decreased when smaller volumes of Haemaccel were infused, which strongly suggests that plasma fibronectin is cleared by means of Haemaccel and does not seem to play a role of opsonin in these conditions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献